Machine for duplicating with axially movable master sheet



y 1965 R. M. FORD ETAL 3,192,855

MACHINE FOR DUPLICATING WITH AXIALLY MOVABLE MASTER SHEET Filed June 19,1963 7 Sheets-Sheet 1 I 09w: age Can/vs.

y 6, 71965 R. M. FORD ETAL 3,192,855

. MACHINE FOR DUPLICATING WITH AXIALLY MOVABLE MASTER SHEET Filed June19, 1963 v 7 Sheets-Sheet 2 O IVkLD Max F01 0 Den; l spcy Ctfiua y 6,1955 R. M- FORD ETAL 3,192,855

MACHINE FOR DUPLICATING WITH AXIALLY MOVABLE MASTER SHEET Filed June 19,1963 '7 Sheets-Sheet 3 y- 1955 R; M. FORD ETAL 3,192,855

momma FOR nurmcmme w'xm AXIALLY MOVABLE MASTER SHEET Filed June 19, 19637 Sheets-Sheet 4 //v ua/vroza 1 0M940 N9! gp flaws ezcy lea/vi y 6, 1965R. M. FORD ETAL 3,192,855

MACHINE FOR DUPLICATING WITH AXIALLY MOVABLE MASTER SHEET Filed June 19,1963 7 Sheets-Sheet 5 July 6, 1965 R. M. FORD ETAL MACHINE FORDUPLICATING WITH AXIALLY MOVABLE MASTER SHEET 7 Sheets-Sheet 6 FiledJune 19, 1963 f Q 21M y 1955 R. M. FORD ETAL 3,192,855

MACHINE FOR DUPLICATING WITH AXIALLY MOVABLE MASTER SHEET Filed June 19,1963 7 Sheets-Sheet 7 n5 &

M/70:5 IOIYFFLD f/g RED Dcms a e (arms United States Patent 3,192,855MACHENE F 311 DWLIQATHNG WITH AXKALLY MQVABLE MASTER SHEET Ronald MaxFord, Abbots Morton, and Denis Percy Crane, (Elton Soiihuil, England,assiguors to Frank R. Ford Limited, London, England, a British companyFiled June 19, 1963, Ser. No. 288,982

9 Claims. (Cl. 101-1325) This invention relates to duplicating machines,hereinafter referred to as being of the kind specified, including arotary printing couple comprising a master cylinder and a pressureroller co-operative therewith, the master cylinder being adapted tocarry a master sheet from which impressions of matter appearingthereon-can be taken onto copy sheets passed through the printingcouple.

The matter appearing on the master sheet may be marked or appliedthereon in the form of hectographic carbon or other similar materialfrom which impressions can be taken onto copy sheets moistened with asolvent, in which case the machine would include a means for moisteningthe copy sheets when passed along an in-feed path to the printing couplepreparatory to entry between the master cylinder and the pressureroller.

In connection with the organisation and administration of manufacturingactivities, and also possibly in other fields, it is often required toreproduce on copy sheets matter appearing in a selected area only ofa'master sheet, possibly in association with constant or heading matterfrom another master sheet, and various constructions of duplicatingmachines of the kind specified have been proposed to meet this generalrequirement.

One such form of duplicating machine of the kind specified includes amaster cylinder having two circumferentially spaced slots in which aredisposed clips for clamping the respective leading margins of a mastersheet and a masking sheet, the latter being secured by the clip of theleading slot (having regard to the direction of rotation of the mastercylinder) so that the masking sheet overlies a part of the master sheetand prevents matter appearing on this part from being transferred to acopy sheet, the extraction of matter being thus confined to the exposedpart of the master sheet. In order to vary the axial position of themaster sheet and hence vaiy'the circumferentially extending zone fromwhich matter is extracted during operation of the machine onto copysheets fed therethrough, the clip which secures the master sheet hasbeen adapted to be moved axially by means of a mechanism disposed in theinterior of the master cylinder.

This arrangement, however, requires that the movable clip shall have alength which is not more than half the axial length of the mastercylinder to avoid restricting the extent to which the sheet held therebycan be shifted axially.

At the end of a series of duplicating operations involving extraction ofmatter from. diiferen't circumferentially extending zones of a mastersheet, the clip is normally left in a predetermined position, usually atone end of the master cylinder. It has, therefore, to be moved back toits starting position before the next series of duplicating operationsare performed. This is because, in most cases, selective extraction ofmatter from a master sheet starts at one boundary thereof and finishesnear the other boundary.

ice

A further limitation of this form of duplicating machine is that, if,for any reason,- it is required to take an impression from the whole ofa full width master sheet, that is one extending for the entire axiallength ofthe master cylinder, such master sheet necessarily has to beheld by a clip other than the movable clip (the latter being only halfor somewhat less than half the length of the master cylinder).Consequently, the leading margin of such full Width master sheet must beheld by the clip normally used for holding the masking sheet. Theportion of the fullwidth master sheet which overlies the movable clipand part of the master cylinder in which s'uch clip operates is thusunuseable for the purposes of duplicating,

owing to the discontinuous or uneven support which would be afforded bythis part of the master cylinder underlying it, iie. that in which themovable clip is mounted.

One object of the present invention is to provide anew or improved formof means for holding master and masking sheets on a master cylinder of aduplicating machine of the kind specified, whereby the disadvantagesabove referred to are avoided or reduced and certain other advantagesare obtained as will hereinafter be apparent from, or will be pointedout in, the following description.

The invention resides in the provision in a duplicating machinecomprising a supporting structure, a rotatable master cylinder having aradialiy outwardly presented'face for carrying at least one master sheetfrom which impressions of matter thereon can be taken, of theimprovement comprising, a first sheet holding means on said mastercylinder forsecuring said master sheet thereon, a second sheet holdingmeans on the master cylinder for securing said masking sheet thereon andspaced circumferentially of said master cylinder from said first sheetholding means, at least one of said sheet holding means including anendless belt having a sheet-engaging face defining one of the boundariesof at least a predetermined portion of the length of an axiallyextending slot in said master cylinder, said belt having projections onits sheet-engaging face adapted to penetrate or indent that one of saidsheets associated therewith, and means for moving said belt alongsaidslot while maintaining said sheet-engaging face preposition after ithas been used for moving the associated sheet in a preceding cycle ofoperationsfof the machine along the length of the slot. 7

'The belt is preferably driven through indexing mechanism which canimpart stepwise movement to the belt along the length of the slot in onedirection or in the other direction selectively, thereby enabling theuser to effect forward stepwise movement of a sheet or reverse stepwisemovement or back spacing of a sheet.

The forward movement may be performed selectively either at will, byuseof a hand-operated member on the machine, or automatically in responseto each cycle of rotation of the master cylinder.

The invention will be further. described by way of example withreference to the accompanying drawing showing an embodiment of theinvention and wherein:

FIGURE 1 is a perspective view of the machine looking towards the frontor side thereof;

FIGURE 2 is a fragmentary view in end elevation of the master cylinderlooking towards the left-hand end thereof, part of the end member andmaster cylinder being broken away to show details of the sheet shiftingdevice;

FIGURE 3 is a fragmentary view showing part of the sheet shifting deviceand actuating mechanism therefor, the view being taken in cross-sectionon the line 3-3 of FIGURE 2;

FIGURE 4 is a view in front elevation of the sheet shifting device andactuating mechanism therefor, the master cylinder being shown in chaindotted lines;

FIGURE 5 is a view in side elevation of the machine unit proper or upperpart of the complete machine shown in FIGURE 1 looking towards theright-hand side, the cover of the side frame member having been removedto show the drive to the master cylinder;

FIGURE 6 is a fragmentary view in cross-section in a vertical planethrough a portion of the master cylinder showing the arrangement ofslots and clips for clamping margins of a master sheet and maskingsheet;

FIGURE 7 is a View in side elevation of the machine unit proper or upperpart of the complete machine shown in FIGURE 1 looking towards theleft-hand side thereof; the cover of the side frame member having beenremoved to show details of the mechanism for selecting the magnitude ofeach step of the stepwise movement imparted by the sheet shifting deviceto the sheet associated therewith when the machine is set for eitherautomatic or hand operation of the sheet shifting device;

FIGURE 8 is a view similar to FIGURE 7 but looking at the right-handside of the machine showing the arrangement of mechanism for controllingthe magnitude of the steps of movement of the sheet shifting device whenthe machine is set for back or reverse spacing of the sheet;

FIGURE 9 is a fragmentary view in vertical crosssection through theoperating member for setting the magnitude of the step through which thesheet shifting device moves the associated sheet; and

FIGURE 10 is a view in side elevation of the parts shown in FIGURE 9.

In this construction the machine may comprise any suitable form of frameor supporting structure 10 including a pair of side frame members 11, 12between which a master cylinder 13 is journalled for rotation about ahorizontal axis. Beneath the master cylinder is a pressure roller 14(FIGURES 7 and 8) having a length extending for the full length of themaster cylinder and at one side of the latter, namely at the front ofthe machine, is provided a tray or table 15 with which is associatedfeed rollers for advancing copy sheets along the infeed path to the nipbetween the master cylinder 13 and pressure roller 14. The machine alsohas a delivery traylSa for receiving the copy sheets returned forwardlybeneath the printing completing any suitable form of sheet returningroller system (not shown).

At a suitable position on the infeed path, the machine incorporatesmeans 16 for applying solvent thereto to moisten the copy sheets, suchmeans 16 comprising moistening roller 17 and liquid supply structure 18,and a moistening pressure roller 19 disposed respectively above andbelow the infeed path. Alternatively, a moistening pad may be employed.In either case the moistening means 16 extends for the full width of themaster cylinder.

The moiste'ning roller 17 and mo-istening pressure roller 19 may bedriven in any suitable manner, for example, by ransmission meansderiving its motion from a cam driven with the master cylinder.

The construction of the machine thus far described in conventional andit will be understood that it may be varied as, for example, byutilisation of a pressure roller which is a fractional length relativelyto the length of the master cylinder and mounted'for axial movementtherealong to register with the particular zone of the mas ter sheet,from which matter is required tobe extracted.

Similarly, fractional width moistening means may be em ployed if desiredin which case such means would be mounted on an axially shiftablecarriage to register with the selected zone.

The frame or supporting structure 10 includes a base unit 9 having sideplates 8 connected by a back wall 7, the side plates 8 includinginwardly projecting enlargements 6 at their upper ends on which sideframe members 11 and 12 of the machine unit proper or upper portion ofthe machine are carried, the base unit is thus of hollow form open atits front and which serves to accommodate at its lower end two operatingpedals 4 and 5 which determine the mode of operation of the sheetshifting device, that is to say whether the latter operatesautomatically once per revolution of the master cylinder or is set to aneutral position. In the latter case the operator may then use ahandoperated actuating mechanism for operating the sheet shifting deviceat will.

Referring now to the master cylinder 13, this is formed, as seen inFIGURE 2, with two circumferentially adjacent axially extending slots,one 20 of which namely that occupying the trailing position, receivesthe leading margin of a textual master sheet from which matter isrequired to be extracted selectively from'certain circumferentiallyextending zones in sequence.

The other slot 21 occupies the leading position having regard to thedirection of rotation of the master cylinder, as seen in FIGURES -2 and6.

The slot 21 receives the leading margins of a masking sheet whichoverlies a portion of the master sheet. The slot 21 also receives theleading margin of a further masking sheet spaced axially from the firstmasking sheet so as to afford a gap or slot between adjacent edges ofthe two sheets through which a selected portion of the textual mastersheet is exposed. The further masking sheet may be constituted by amaster sheet which on its outer face bears constant or heading datawhich would usually be disposed adjacent to the gap or slot.

These various sheets are not shown in FIGURE 2 but in FIGURE 6fragmentary portions of the textual master sheet 22 and the masking 23are shown as single lines spaced away merely for the sake of clarityfrom the circumferential face of the master cylinder 13. The leadingmargins of these sheets which enter the slots 21 are not shown in theslots in order to avoid obscuring certain of the parts present in thebase of the slot 20.

In FIGURE 1 there are shown trays or. guide plates.

24 and 25 for these various sheets. These trays or guide plates arepreferably made of a transparent material such as a suitable syntheticresin and they are arranged tangentially,'or approximately so, to thesurface of the master cylinder with their lower ends spacedcircumferentially therewith to register respectively with the entrancesto the slots 20 and 21. The tray or guide plate 24 receives and supportson its upwardly and forwardy presented guide face the textual mastersheet 22 preparatory to. insertion of the latter into the slot 20 whilethe tray or guide plate 25 receives in one of its zones 26 the maskingsheet, again laid on the upper forwardly presented face, and on theother of its zones 27 the further masking sheet which, as previouslyindicated, may be a master sheet bearing constant or heading data.

The tray or guide plate .24 may be marked with two parallel lines 28 toindicate the gap or exposure slot through which matter is to beextracted from the textual master sheet, the position and width of thisgap or' slot being in effect defined by the adjacent edges of the twomasking sheets which are separated by a spacer bar 29 secured to theupwardly and forwardly presented face of the tray or guide plate 25,preferably centrally of the length of the latter.

It will be understood that the master cylinder 13 is faces of the traysor guide plates 24 and 25 respectively,

and in this position clips associated respectively with the slots arecaused to be moved to an open position to allow the various sheets to bemoved into the slots.

The two masking sheets, of which one may be a master sheet bearingconstant or headed data, are secured in the slot 21 by means of clips ofconventional form, as seen at 30.

The slot 21 is formed in an enlargement 31 of the wall of the mastercylinder which is thickened by inward radial extension and the clip isof T-shape in side elevation, as seen particularly in FIGURE 6,' so thatthe slot 21 attords an entrance or radially extending branch 21a ofwhich the mouth is in the circumferential face of the master cylinder,and a transverse or circumferentially extending branch 21b at the innerend of the nadially extending branch. The slot 21 is thus of L-shape, asviewed in side elevation, and the sheets moved into this slot thereforetake up a stepped form in cross-section, thereby stiffening the sheetslocally and minimising the risk of distortion or crumpling.

The clip 3% is guided by means ofthe stem portion 39a for radialmovement in the enlargement 31 and is urged radially inwardly bysprings, such as that seen at 32, carried by a guide pin 33 of which thehead is disposed in a bore in the clip 30 and which at its inner endscrews into the enlargement 31. i

Movement of the clip 30 between an open and close position is efiectedby a cam 34 (-FIGURE 8) pivoted on a pin 35 carried by side plate 36whichforms part of the side frame member 12;. This cam can be rockedabout the pin 35 by an operating lever 3'7 and carries two studs 38 and39 which contact levers 4t and 41 pivoted on pins 42 and 43 on themaster cylinder.

The lever 41 engages the inner end of the stem 30a of the clip 30 wherethis projects axially beyond the inset or recessed end members 13a ofthe master cylinder so that movement of the lever 37 can rest the clip30 against the pressure of springs 32.

A similar clip 44, with a stem 44a guided in the enlargement 31, isprovided to form the outer boundary of the slot 20 which again has aradially extending branch 20a and a circumferentially extending branch29b.

The clip 44 is urged inwardly by a coiled compression 3 spring 45disposed on a guide pin 46, the outer end of which is screwed intothe'stem 44aand the shank of which passes slidably through a guide bar47 fixed in the enlargement 31.

The clip 44 is movable from its closed position towards which it isurged by the spring 45 by the operating mechanism comprising the lever37 already referred to, cam .34, pin 38 and lever 40.

At the inner side or bottom of the transverse or circumferentiallyextending branch 20b of the slot 29 there is provided a sheet shiftingdevice for moving the textual master sheet axially of the slot. Thisshifting device includes a member extending along the length of the slotand which is movable along the length of the slot, selectively in eitherdirection, and selectively in increments of movement of any of a numberof pro-selected magnitudes. The belt is preferably of endless formalthough this "is not essential. One run 48 of the belt lies in thebottom of the slot 24) and an opposed parallel run 49 is disposed at aposition inset radially from the wall of the master cylinder. Pulleys 5Gand 51- are provided in the interior of the master cylinder adjacent toopposite ends thereof for supporting, driving and guiding the belt whichthus moves in a plane radial, or approximately radial, to the axis ofrotation of the master cylinder. I

At its outer surface the belt may be provided with a plurality ofoutwardly projecting pins or spikes 52 which can penetrate the leadingmargin of the textual master sheet so as positively to move this alongthe length of the slot 29. Alternatively the outer face of the beltcould be formed with transverse ribs or other forms of tread to indentor slightly deform the leading margin without necessarily penetratingthis and so assist movement along the length of the slot.

The operative or outer run 48 of the belt is urged radially downwardlyby means provided in the base of the slot specifically for this purposeand which comprise a pressure strip or bar 53 carried by guide pins 54,'screwing into the enlargement 31, and on which are disposed coiledcompression springs 55 acting between the underside of the bar 53 andthe inner wall'of a recess in the enlargement 31 in which the bar ismounted.

. The belt may be made of any suitable material, for example, it may beof natural or synthetic rubber or a synthetic resin having the requisitedegree of flexibility. It could also be in the form of a sprocket chain,or flexible of a series of sliding shoes arranged end-to-end and guidedalong an endless trackway formed in the base of the slot and having areturn portion in the interior of the master cylinder.

Reverting to the construction specifically illustrated, it will beobserved that positive drive is established between the pulleys 59 and51 and the belt by the provision of teeth or castellations 56 at theinner side of the belt which mesh with corresponding recesses 57 and 58in the grooves atiorded at the peripheries of the pulleys 50 and 51respectively. u

The pulleys themselves are supported by trunnion plates or brackets suchas those seen at 59, do. The brackets or trunnion plates include baseportions, such as seen at 61 of FIGURE 2, secured by bolts 62 tomounting arms 63 carried by the end member 13a of the master cylinder.

For imparting the requisite stepwise or incremental I movement to thepulleys 50 and 51 and hence to the belt there is associated with eachpulley, pawl and ratchet mechanism which, sinceit is identical at eachend of the master cylinder, will be described in relation to only one ofthe pulleys, namely the pulley 50.

This mechanism comprises a ratchet wheel 64 which is fast with theassociated pulley, and a pawl 65 mounted on an oscillatory carrier plate66, the axis of oscillation of which is co-axial with that of theratchet wheel 64 and.

pulley 50.

The pawl 65 is normally retained at one extremity of its movement, asseen particularly in FIGURE 3, with its tooth 65a out of mesh with theteeth of the ratchet Wheel 64 by means of a tail 65b on the pawl whichmakes contact witha trip block or projection 67 mounted on the baseplate of the trunnion plate or bracket 59. The trip block 67 isadjustable lengthwise by means of guide slots 68 formed in the bracketortrunnion plate 59, and threaded clamping elements 69 extending throughthese slots and screwing into the trip block.

This enables the clearance between the tooth 65a of the. pawl and thepath of movement of the tips of the teeth of the ratchet wheel to be setso that, Whilst the ratchet'wheel is unobstructed as to its rotationwhenthe pawl is in the position shownin FIGURE 3, there is almost instantengagement of the pawl to drive the ratchet wheel when the oscillatorycarrier plate 66 is rotated from the position shown in FIGURE 3.

The purpose of retaining the pawl out of mesh with the ratchet wheel isto ensure that the belt can be driven by the pawl and ratchet mechanismand pulley at either end of the master cylinder without encounteringobstruc- 7 tion from the pawl and ratchet mechanism and pulley. at theother end.

Oscillatory movement is imparted to the pawl carrier 66 by means of alink 70 pivotally connected by means of a pin 71 at one of its ends tothe pawl carrier, and pivotally connected at its opposite end to aspigot 72 projecting axially from a stud 73 fixed to one arm 74 of anoscillatory lever 75 rotatable on a circular boss 76 at the adjacent endof the master cylinder.

A second arm 77 onthis lever is pivotally connected to a cam plate 78which can rock about the axis of a mounting bolt 79 carried by a plate80 fixed on the master cylinder boss 76 and rotating with themaster-cylinder.

The cam plate 78 has a pin and slot connection as indicated at 81 withthe arm 77 of the lever 74 and the lever 7 is urged to rotate in aclockwise direction, asseen in FIGURE 2, by means of a coiled tensionspring 82 connected between the arm 77 and the bolt 79 on the fixedplate 80 so as to normally maintain the. parts of the actuatingmechanism for the belt in the neutral or disengaged position shown inFIGURE 3.

The cam plate 78 has a straight edge or face $3 which at one or theother end of the master cylinder is brought into contact with anactuating cam follower, as hereinafter described, to impart therequisite increment of movement to the belt in one direction of travelof the run 48 of this belt along the slot 20, or in the other directionas may be required.

The cam plate 78 and the associated cam follower element are so arrangedin each case as to be set relatively in any of a plurality of differentpositions affording different degrees of lost motion so that the extentof the oscillatory movement" impartedto the cam plate 78 varies betweenone setting and another and thereby enables the user to preset the stepor increment of movement to be transmitted to the run 43 of the belt.

This arrangement is adopted whether the actuating mechanism is arrangedfor automatic operation, once per cycle of operation of the cylinder, isoperable at will, or is used for reverse or back spacing movement of thebelt.

Referring firstly to operation of the belt automatically, the mechanismfor effecting this is seen in FIGURE 7.

The cam follower required to contactthe straight cam face 83 of the camplate 78 during rotation of the master cylinder 13 comprises a roller 84preferably adjustable in position alonga slot'85 in a triangular plate86, pivoted about a horizontal axis by means of a bolt 87 to the sideplate 88 which forms part of the side frame member 11 or" the machine.

The angular position of the plate 86 about the bolt is controlled bymeans of a strut S9 whichrat one end carries a stop piece 93 which canbe brought into abutting engagement with any one of a plurality of stopmembers 91a, 91b, 91c carried by a rotary setting device 92 whereinthree such stop members are shown by way of example.

To set the machine for automatic operation of the sheet shifting devicethe foot pedal is depressed. This is pivotally connected at its lowerend to a link 93, the upper end of which is pivotally connected to alever 94 itself pivotally connected to the upper end of'link 95 so thatit can rotate about a pin 96.

in the position of the parts shown in FIGURE 7, when the pedal 5 hasbeen depressed, resultant downward movement of the link 93 has causedthe lever 94 to rotate from a horizontal position to a nearly verticalposition, as seen in FIGURE 7, in which'the right-handend of the leveris engaged beneath an arm 97 on a rocker 98 pivotally mounted on a stud99 for movement about a horizontal axis. At its lower end the rocker 98carries a fixed arm 199 which forms part of an'over centre or togglemechanism comprising a further armor link 101 slidable on a pin 102carrying a spring 103 and supported by a pivot block on a lever 104.

The raising of the arm 97 and clockwise movement of the rocker 98 causesthe strut 89-to be moved to the right through pivotal connection by apin 105 at the upper end of the rocker with the strut 89. Movement isarrested when the stop piece is brought into abutment with one of thestop members such as 91a.

This sets the triangular plate 86 in a predetermined position in whichthe cam follower roller 84 is positioned for engagement with thestraight cam face 83 at a particular position along the latter from itsupper end and thereby imparts a particular value of oscillation to thecam plate 78.

When it is desired to set the mechanism to the neutral position, .inwhich the cam follower roller 84 is wholly out of the path of movementof the cam plate 78, the foot pedal 4 is depressed. This pedal isconnected pivotally to the lower end of the link so that the latter ismoved downwardly relatively to the link 93. It will be understood thatthe pedal 5 may be fixed to a board or structure rockable abouthorizontal axes at the forward edges of the pedals, and that the pedal 4is separately hinged to this board or structure; A link connection fromthe pedal 5 (or the board or structure) to means for controllingoperation of. the machine thus ensures. that the machine will executeone cycle of operation whenever eitherpedal is depressed, and that sheetshifting will be automatic when the pedal 5 is used and non-automatic,that is by hand, when the pedal 4 is used.

Also, depression of, the pedal restores the lever 94 to an approximatelyhorizontal position and at the same time a cranked portion presenting adownwardly facing shoulder 95a at the upper end of the link 95 engages astop member 10941 on the arm 160, thereby freeing the arm 97 fordownward movement and positively oscillating the rocker 93 in ananti-clockwise direction (as viewed in FIGURE'7).

The strut 89 is moved to the left, and the cam follower roller 84 isbrought to the lower end of its path of travel clear of the path ofmovement of the cam face 83.

A coiled tension spring 1% serves to maintain the parts in the positionshown in FIGURE 7 when the pedal 5 has been depressed to set the machinefor automatic operation.

The member 92 may comprise a nut and the stop members 91a and 910 maycomprise bolts screwed into threaded holes in respective faces ofthenut. As seen particularly in FIGURE 9, an operating member is providedfor setting the nut in any of a number of angular positions.

For this purpose the nut is carried by a bush 107 formed with a spigot168 on to which screws a clamping nut 109.

Locking mechanism is provided comprising a sliding pin 110 extendingthrough a bore in the nut 92 to engage in any one of a plurality ofangularly spaced holes, of which one is seen at 111, in the plate 88.

To withdraw the pin 110 from an associated one of these holes, apush-button 112 is provided which can be depressed against the pressureof a compression spring 113 in the interior of the bush and whichcarries a stem 114 connected by a cross piece 115 to the pin 110.

The bush 107 is preferably formed witha notch 107a to expose selectivelyany one of a series of markings such as that indicated at 116, showingthe value or" the increment or step of spacing pertaining to eachselected position of the rotary member or nut 92.

For operating the sheet shifting device manually, or at will, a secondtriangular plate 117 is provided pivotally mounted on the plate 88 bymeans of a bolt 118 and carrying a canrfollower roller 119.

The plate 117 can be oscillated about the bolt 118 by means of amanually operable member 120 (FIGURES 7 and 1) which is fixed to a leverarm 121 on the inner side of the plate 88. The lever arm 121 has a pinand slot connection 122 with an arm 123 fixed to the triangular plate117.

The extent of oscillatory movement which can be imparted is controlledby a rotary member 124 and a series a 9 of stop members 125a, 125b, 1250similar to those al-' ready described in connection with FIGURE 9 andwhich can be set selectively in the path of movement of a stop arm126'fixed to the shaft or spindle 127 of the operating member 12% 7Referring now to FIGURE 8 there is shown therein an actuating mechanismfor the sheet shifting device for use in operating the sheet shiftingdevice for reverse motion or back-spacing of the textual master sheet.This operation is performed manually by means of an operating member inthe form of a lever 128Vwhich is pivoted bymeans of a bolt 129 to theside plate 36 and at its lower end carries a cam follower roller 13ft.Movement of the lever 128 causes the roller to make contact with the camface E3 of cam plate 78 at the right-hand end of the master cylinder tocause the cam plate to oscillate and impart the requisite step ofmovement to the run 48 of the belt in a direction reversely of thatproduced by operation of the cam plate 78 at the left-hand side of themaster cylinder.

The magnitude of the step thus imparted is determined by the degree ofangular movement of the lever 128 which is permitted from its initialposition as shown in FIGURE 8. r 1

This is controlled in turn by the angular position of a stop bar 131pivotally mounted on a stud 132 at the outer side of the side plate 36and connected to a coiled tension spring 133 extending between the bar131 and an anchor pin 134 on the side plate so as to cause the stop barto rotate in a clockwise direction as seen in FIGURE 8.

Movement of the lever 128 also in a clockwise direction is arrested bycontact between a lug 128a extending at right angles from the plane ofthe lever stem which is formed of strip metal being brought into contactwith the corner 131a of the stop bar 131. V p

The initial gap or space between the lug 128a and the corner 131a iscontrolled by the position of a rotary setting member 135 constructedand adapted to operate in a manner similarto that illustrated in FIGURE9, and which carries a plurality of stop elements 136a, 1361: and 136ain the form of screws or bolts projecting radially for differentlengths.

The arrangements for driving the master cylinder are illustrated inFIGURE 5.

The master cylinder is driven by means of a belt 137 passing round apulley 138 fast with the input or driving member of a single revolutionclutch 139, and round a pulley 14% on a counter-shaft 141 to which isfixed a larger pulley 142 which in turn is driven by a belt 143 from apulley 144 on a driving shaft 145. The driving shaft may be coupleddirectly to the armature of an electric motor or driven therefrom by anysuitable form of transmission means.

Rotating with the driven or output member of the clutch is a dog ortooth 146 which cooperates with two pawls 147 and 148 to arrest themaster cylinder in a predetermined position with its slots inregistration with the trays 24 and as already described.

The pawl 147 comprises a bar which can pivot about a pin 149 and ispositively controlled by means of a rigid, right-angled arm structure15% fixed to the pawl 147 to swing therewith about the axis of the pin149 and which carrie a pin 151 engaged by the upwardly extending arm 152of a bell crank lever whereof the other arm 153 is pivotally connectedto a downwardly extending link 154. The link 154- is connected at itslower end to the foot pedal 5 or board or structure on which this isfixed, so that upon depression of the foot pedal 5 the link is lowered,the bell crank lever rotated clockwise and the pawl 147 released fromthe dog or tooth 146 to allow the clutch to rotate.

The pawls 14-8 also comprises a bar pivoted on a pin155 and urged forrotation in an anti-clockwise direction by a coiled tension spring 156end of this pawl and an anchor pin 157 on the plate 36.

A release of pressure from the foot pedal 5 allows the latter to rise byspring means and restores the pawl 147 to its initial position as shownin FIGURE 5, so that the dog or tooth 146 is automatically brought torest between the two pawls in the position shown, the spring loaded pawl148 preventing any oscillation or reverse movement of the mastercylinder.

The operation of the machine may be summarised as follows.

\Vhen the foot pedal 5 is depressed the machine is set for automaticspacing of the textual master sheet in a forward direction, that is tosay from right toleft of the master cylinder as viewed from the front.

This takes place by movement from right to left of the run 4s of thebelt. Such movement is derived from oscillation in a clockwise direction(relatively to the master cylinder of the cam plate 78 at the left-handside of the master cylinder) which in turn is brought about by contactwith the cam follower roller 84 on the plate 86.

The plate is held in a pre-selected position determined by the positionof the rotary setting member 92 by means of a strut 8 9 which is movedto the right by rocker 93 automatically upon depression of the footpedal 5.

When it is desired to revert to the neutral position of this actuatingmechanism the pedal 4 is depressed to move the link 95 downwardly so asto engageits shoulder 95a with the stop member ltitia and move therocker 98 to the left at its upper end. This movement is transmitteddirectly to the strut S9 and causes the triangular plate 86 to be movedclockwise to a position where the cam follower roller 84 is at the lowerend of'its path of travel and is disposed out of the path of movement ofthe cam plate 78.

Hand spacing can be effected by means of operating lever 1215 producingoscillatory movement of triangular plate 117 to bring the cam followerroller 119 thereof in contact with the cam plate 78. a It-will beunderstood that when the master cylinder is in its stopped position thestraight cam face 83 will be suitably disposed in the path of movementof the 1. In a duplicating machine comprising a supporting 7 structure,a rotatable master cylinder having a radially outwardly presented facefor carrying at least one master sheet from which impressions of matterthereon can be taken, and for carrying at least one masking sheet, and apressureroller co-operative with said master cylinder; the improvementcomprising, i

a first sheet holding means on said master cylinder for securing saidmaster sheet thereon,

a second sheet holding means on said master cylinder for securing saidmasking sheet thereon and spaced circumferentially of said mastercylinder from said first sheet holding means,

at least one of said sheet holding means including an endless belthaving a sheet-engaging face defining one of the boundaries of at leasta predetermined portion of the length of an axially extending slot insaid master cylinder,

means for moving said belt comprising pulleys disposed at opposite endsof said slot and around which said endless belt passes, i

connected between the lower I indexing mechanisms mounted on said mastercylinder respectively for rotating said pulleys in opposite directions,said indexing mechanisms each comprising a pawl element and a ratchetelement, said indexing mechanisms including means for automaticallydisengaging each pawl from its associated ratchet element uponcompletion of a stepwise driving movement so that the pulleys are freeto rotate in either direction according to which one of said indexingmechanisms is selected for actuation,

and actuating mechanism mounted on said supporting structure of saidmachine .for selectively operating either of said indexing mechanisms.

2. In a duplicating machine comprising a supporting structure, arotatable master cylinder having a radially outwardly presented face forcarrying at least one master sheet from which impressions of matterthereon can be taken, and a pressure roller, co-operative with saidmaster cylinder, the improvement comprising,

a first sheet holding means on' said master cylinder for securing saidmaster. sheet thereon,

a second sheet holding means on the master cylinder for securing saidmasking sheet thereon and spaced circumferentially of said mastercylinder from said first sheet holding means,

at least, one of said sheet holding means including an endless belthaving a sheet-engaging face defining. one of the boundaries of at leasta predetermined portion of the length of an axially extending slot insaid master cylinder,

said belt having projections on its sheet-engaging face adapted topenetrate or indent that one'of said sheets associated therewith,

and means for moving said belt along said slot while maintaining saidsheet-engaging face presented along said portion.

. 3. In a duplicating machine comprising a supporting structure, arotatable master cylinder having a radially outwardly presented face'forcarrying at least one master sheet from which impressions of matterthereon can be taken, and for carrying at least one masking sheet, and

a pressure roller co-operative with said master cylinder;-

the improvement comprising,

a first sheet holding means on said master cylinder for securing saidmaster sheet thereon,

a second sheet holding means on said master cylinder for securing saidmasking sheet thereon and spaced circumferentially of said mastercylinder fromsaid first sheet holding means,

at least one of said sheet holding means including anelongatedsheet-engaging member mounted on said master cylinder and having asheet-engaging face defining, and constantly presented along at least apredetermined portion of the length of, one of the boundaries of acircumferential branch of an axially extending slot in said mastercylinder,

surfaces on said master cylinder defining a radial branch of said slot,such radial branch communicab' ing at its inner end with saidcircumferential branch and connecting the latter to said radiallyoutwardly presented face of saidmaster cylinder,

and means for moving said sheet-engaging member along said slot whilemaintaining said sheet-engaging face presented along said portion.

4. The improvement claimed in claim 3 wherein a pressure member is alsodisposed in said circumferentially extending branch of said slot at thatside of said sheetengaging member remote from its sheet-engaging face,

and wherein spring means are provided for urging said pressure member ina direction towards said sheetengaging member.

5. In a duplicating machine comprising a supporting structure, arotatable master cylinder havinga radially 12 outwardly presented facefor'carrying at least one master sheet from which impressions of matterthereon can be taken, and, for carrying at least one masking sheet, anda pressure roller co-operative with said master cylinder;

the improvement comprising,

a first sheet holding means on said master cylinder for securing saidmaster sheet thereon,

a second sheet holding means on the master cylinder for securing saidmasking sheet thereon and spaced circumferentially of said mastercylinder from said first sheet holding means,

at least one of said sheet holding means including an elongatedsheet-engaging member mounted on said master cylinder at a positioninwardly of its radially outwardly presented face, said sheet-engagingmember extending axially of said master cylinder and having a sheetengaging face defining one of the boundaries of at least part of thelength of an axially extending slot in said master cylinder,

said sheet-engaging member being spaced in a direction normal to itssheet-engaging face from a further boundary face of said slot by adistance providing freedom for movement of said master or maskingsheetalong said slot,

longitudinally spaced projections on said sheet-engaging memberextending at least partly across said slot between said boundary faces,

and means for moving said sheet-engaging member longitudinally of saidslot.

6. The improvement claimed in claim 5 further comprising an elongatedaxially extending clip mounted on said master cylinder and having aportion disposed radially outwardly of, but spaced radially from, saidsheet'engaging member to define in combination therewith acircumferentially extending branch of said slot, said clip having acircumferentially presented face opposed to, and spacedcircumferentially from, a face on the master cylinder to define a radialbranchof said slot communicating at its inner end with saidcircumferential branch,

means for moving said clip outwardly of, and towards, said radiallypresented face of said master cylinder to facilitate insertion of amargin of said master or masking sheet into said radial andcircumferentially extending branches.

7. The improvement claimed in claim 1 wherein said actuating mechanismcomprises:

a manually operable member operatively engageable with one of saidindexing mechanisms for effecting step-by-step movement of said beltmanually,

and power operated mechanism movable alternatively into operative andinoperative positions and operatively engageable in the former of thesepositions with said one indexing mechanism for effecting stepby-stepmovement of said belt automatically in response to each rotation of saidmaster cylinder. 8. The improvement claimed in claim 7 wherein saidactuating mechanism further comprises a manually operable memberoperatively engageable with the other one of said indexing mechanismsfor effecting step-by-step movement of said sheet engaging member in thereverse direction to that effected by the first said manually operablemember and said one indexing mechanism.

9. The improvement claimed in claim 8 wherein said actuating mechanismcomprises a cam element and follower element, one of such elements beingmounted on said master cylinder and operatively connected with said oneindexing mechanism, the other of said elements. being mounted on saidsupporting structure of said machine, mounting meansfor said otherelement for enabling it tobe positionally adjusted into any of a numberof positions providing different respective amounts References Cited bythe Examiner of clearance or lost motion with respect to said ele- IUNITED STATES PATENTS ment on said master cylinder, I manually operablesetting devices each movable into 2,724,330 11/ 55 Brown et each of aplurality of positions and operatively con- 5 2,997,949 8/61 Ritzerfeldet a1. 101-l32.5

nected with said positionally adjustable element FOREIGN PATENTS throughtransmlsslon means assoclateo respectwely I with said manually operablemember and said power- 530,313 8/58 yoperated mechanism for setting themagnitude of the step-by-step movement effected thereby. 10 EUGENECAPOZIO Primary Exammer-

1. IN A DUPLICATING MACHINE COMPRISING A SUPPORTING STRUCTURE, AROTATABLE MASTER CYLINDER HAVING A RADIALLY OUTWARDLY PRESENTED FACE FORCARRYING AT LEAST ONE MASTER SHEET FROM WHICH IMPRESSIONS OF MATTERTHEREON CAN BE TAKE, AND FOR CARRYING AT LEAST ONE MASKING SHEET, AND APRESSURE ROLLER CO-OPERATIVE WITH SAID MASTER CYLINDER; THE IMPROVEMENTCOMPRISING, A FIRST SHEET HOLDING MEANS ON SAID MASTER CYLINDER FORSECURING SAID MASTER SHEET THEREON, A SECOND SHEET HOLDING MEANS ON SAIDMASTER CYLINDER FOR SECURING SAID MASKING SHEET THEREON AND SPACEDCIRCUMFERENTIALLY OF SAID MASTER CYLINDER FROM SAID FIRST SHEET HOLDINGMEANS, AT LEAST ONE OF SAID SHEET HOLDING MEANS INCLUDING AN ENDLESSBELT HAVING A SHEET-ENGAGING FACE DEFINING ONE OF THE BOUNDARIES OF ATLEAST A PREDETERMINED PORTION OF THE LENGTH OF AN AXIALLY EXENDING SLOTIN SAID MASTER CYLINDER, MEANS FOR MOVING SAID BELT COMPRISING PULLEYSDISPOSED AT OPPOSITE ENDS OF SAID SLOT AND AROUND WHICH SAID ENDLESSBELT PASSES, INDEXING MECHANISMS MOUNTED ON SAID MASTER CYLINDERRESPECTIVELY FOR ROTATING SAID PULLEYS IN OPPOSITE DIRECTIONS, SAIDINDEXING MECHANISMS EACH COMPRISING A PAWL ELEMENT AND A RATCHETELEMENT, SAID INDEXING MECHANISMS INCLUDING MEANS FOR AUTOMATICALLYDISENGAGING EACH PAWL FROM ITS ASSOCIATED RATCHET ELEMENT UPONCOMPLETION OF A STEPWISE DRIVING MOVEMENT SO LTHAT THE PULLEYS ARE FREETO ROTATE IN EITHER DIRECTION ACCORDING TO WHICH ONE OF SAID INDEXINGMECHANISMS IS SELECTED FOR ACTUATION, AND ACTUATING MECHANISM MOUNTED ONSAID SUPPORTING STRUCTURE OF SAID MACHINE FOR SELECTIVELY OPERATINGEITHER OF SAID INDEXING MECHANISMS.